The Rock Island 49176 ACT-MAG is a 17-round 9mm detachable magazine engineered for full-size Smith & Wesson M&P handguns. Built to the same specifications and tolerances as factory S&W magazines, this blued steel magazine delivers the capacity and reliability you need for duty, competition, or training without breaking the bank. If you run an M&P in 9mm Luger and want dependable backup magazines or a spare set for your rotation, this is a no-nonsense choice backed by proven manufacturing standards.

The steel body paired with a polymer base plate strikes a balance between durability and weight. The flush-fit design means no excess magazine hanging below the grip—it sits clean on a full-size M&P frame, so you get maximum capacity without awkward profile or printing issues if you're carrying. Feeding has been proven reliable across thousands of rounds in the field, making these the kind of magazines you can trust when it matters.

Rock Island (Armscor) has been in the ammunition and components business for decades, and this magazine reflects that manufacturing pedigree. For shooters who want factory-spec reliability on a practical budget, the ACT-MAG delivers. Stock several for your range box, duty rig, or defensive carry setup.

Key Features

• 17-round capacity optimized for full-size M&P 9mm handguns
• Blued steel construction for corrosion resistance and durability
• Polymer base plate for lightweight handling and easy disassembly
• Flush-fit design with no protrusion below the grip
• Manufactured to factory S&W specifications and tolerances

Specifications

Frequently Asked Questions

Will this magazine work with my Smith & Wesson M&P 9mm?

Yes. The ACT-MAG is designed for full-size S&W M&P handguns chambered in 9mm Luger and is manufactured to factory S&W specifications and tolerances, ensuring reliable fit and function.

What makes this magazine different from factory Smith & Wesson magazines?

The ACT-MAG is built to the same specifications and uses comparable high-quality manufacturing materials as factory S&W magazines. The practical difference is affordability—you get factory-spec reliability without the OEM price tag.

Is the 17-round capacity standard for full-size M&P magazines?

Yes. The 17-round capacity is standard for full-size M&P 9mm handguns, and this magazine's flush-fit design means it sits perfectly with the grip without excess protrusion.

Can I use these magazines for duty or defensive carry?

The ACT-MAG meets factory S&W specifications and tolerances and has proven reliable in the field. Many shooters do use them for duty, training, and defensive applications; however, magazine reliability can depend on maintenance and individual firearm handling, so test them thoroughly in your specific pistol.